应急照明包括疏散照明、安全照明和备用照明。正常照明故障至应急照明自动投入的时间，安全照明不应大于0.5s，疏散照明和备用照明不应大于15s。()
参考答案：对
选择适当的代词填空。
1. What is ______________ (she, her) name?
2. ______________ (Our, We) country is China.
3. My brother likes to skip with ______________ (he, his) skipping rope.
4. ______________ (It's, Its) capital city is Canberra.
5. I know about the Canada's flag. ______________ (It, It's) has a leaf.
在电火花加工前，应怎样进行模坯的准备？
